Vaccines are not causing microcephaly in babies.

There is no evidence linking any vaccine to the increases in
microcephaly cases that were observed first in French Polynesia during
the 2013-2014 outbreak and more recently in northeastern Brazil.

An extensive review of the literature published in 2014 found
no evidence that any vaccine administered during pregnancy resulted in
birth defects. The Global Advisory Committee on Vaccine Safety, which
provides independent scientific advice to the World Health Organization
(WHO) on vaccine safety issues, reached a similar conclusion in 2014.

In addition, national regulatory agencies are responsible for
ensuring that products released for public distribution, such as
vaccines, are evaluated properly and meet international standards of
quality and safety. WHO assists countries in strengthening their
national regulatory systems:

An insecticide called pyriproxyfen does not cause microcephaly

A team of WHO scientists recently reviewed data on the
toxicology of pyriproxyfen, one of 12 larvicides that WHO recommends to
reduce mosquito populations. It found no evidence that the larvicide
affects the course of pregnancy or the development of a fetus. The US
Environmental Protection Agency and EU investigators reached a similar
conclusion when they carried out a separate review of the product.

Larvicides are an important weapon in the public health
practitioner’s arsenal. Especially in cities and towns with no piped
water, people tend to store drinking water in outdoor containers. These
sources of water, as well as standing water that may collect in garbage,
flower pots and tyres, serve as ideal breeding grounds for mosquitoes.

Larvicides such as pyriproxyfen are often used in containers
where people store water to kill the mosquito in its larval stage. When
people drink water from containers that have been treated with
pyriproxyfen, they are exposed to the larvicide – but in tiny amounts
that do not harm their health. Moreover, 90% - 95% of any larvicide
ingested is excreted into the urine within 48 hours. This product has
been used since the late-1990s without being linked to microcephaly.

The Zika outbreak and unusual increase in
microcephaly cases in Brazil has nothing to do with the recent releases
of genetically modified mosquitoes in Brazil.

There is no evidence that Zika virus disease or microcephaly
in Brazil is caused by genetically modified mosquitoes. In genetically
modified mosquitoes, the genes of male mosquitoes are modified. Because
of the modification, when they mate with female mosquitoes, their larval
offspring cannot survive. This practice is designed to control mosquito
populations.
WHO encourages affected countries and their partners to boost
the use of current mosquito control interventions as the most immediate
line of defence, and to judiciously test the new approaches that could
be applied in future.

Sterilized male mosquitoes are not contributing to the spread of Zika.

A technique being developed to stop Zika is the mass release
of male mosquitoes that have been sterilized by low doses of radiation.
When a sterile male mates, the female’s eggs do not survive. The
technique has been successfully used, on a large scale, to control
insect pests that threaten agriculture. There is no evidence that the
technique has been associated with increases in microcephaly cases or
other human anomalies or defects.
WHO encourages affected countries and their partners to boost
the use of current mosquito control interventions as the most immediate
line of defense, and to judiciously test the new approaches that could
be applied in future.

Bacteria used to control the male mosquito population are not spreading Zika further

Bacteria such as Wolbachia bacteria are used to control
mosquito populations; they do not infect humans or other mammals.
Wolbachia bacteria are found in 60% of common insects, including
butterflies and fruit flies. Mosquitoes carrying Wolbachia bacteria have
been released in several places, including Australia, Brazil, Indonesia
and Viet Nam, to help control dengue (which is transmitted by the same
mosquito that transmits Zika). When females mate with males carrying the
bacteria, the eggs do not hatch, thus supressing mosquito populations.

Fish can help stop Zika.

Some countries affected by Zika and dengue are using
biological methods as part of an integrated approach to mosquito
control. El Salvador, for example, with strong support from fishing
communities, is introducing larvae-devouring fish into water storage
containers.